How Accurate is Fitbit Charge 2, 3, 4, HR, Flex, Flex 2, Alta, HR, Ace 2 Calorie Burn?

How accurate is Fitbit charge 2, 3, 4, hr, flex, flex 2, Alta, hr, ace two calorie burn

Are you satisfied with the services of the Fitbit Charge smartwatches? Do you have any kind of doubt regarding the calorie burn calculation of the Fitbit smartwatches? We know that the machine equipment is not entirely correct and accurate, but how accurate. 

In this article, we will discuss the methods through which you can find out the calorie burn through Fitbit watches, and also, we will discuss the accuracy of these devices. 

As we all know that nowadays, there are many smartwatches present in the market which tells you about your health, heart rate, calorie burn, steps you have walked, and many more. However, these devices are not entirely accurate. 

If you are a Fitbit user and want to know how accurate rate your device is, then read this article till the end.

Is the Calorie Burn Feature of Fitbit Watches Useful?

If you own a Fitbit watch, you will be able to operate many functions like controlling the music, monitoring your heart rate, O2 monitoring, and many more. However, one of the best features of the Fitbit watch is calculating the calorie burn. 

You can see the option on the watch of the calorie burn, and the watch will keep track of your activity and give you the result of how many calories you have burned during that time. This feature is helpful for those people who like to keep a check on their health and physical activities. 

However, in a recent article, it is shown that the Fitbit and other smartwatches are not 100% accurate, but that doesn’t mean that it is not helpful. Now, let’s talk about the different models of the Fitbit watches and see how accurate they are. 

How to Check the Calorie Count in Fitbit Watches?

Operating the Fitbit watches is easy as all the options are given on the dashboard of the watch screen. The watch calculates your heart rate and takes the necessary information about you like weight, height, gender, and much other necessary information. 

After getting the information, it monitors your day-to-day activity and heart rate. Based on these reports, the Fitbit watch prepares the statistics regarding your calorie burn at the end of the day. 

As there are many models in the Fitbit watches market, each model comes with a slightly different feature. So, let’s find out about the accurate rate of different models of Fitbit watches. 

How Accurate is Fitbit Charge 2 Calorie Burn?

Fitbit Charge 2 is one of the most selling products of the Fitbit brand as this product is loved by every consumer from different countries. To check the Calorie burn, you need to follow these steps:

  • First, you need to connect the Fitbit with your device through Bluetooth. 
  • After that, open the application of the Fitbit.
  • Put your information that is required by the app to measure your BMI.
  • The device will monitor your BMR and other body functions, and it will show you the report of your calorie burned. 

In Fitbit Charger 2, the accuracy rate is underestimated by 4% while running, and while walking, the accuracy rate is overestimated by 50%. 

How Accurate is Fitbit Charge 3 Calorie Burn?

The system of calculating the calorie burn remains the same in every model of the Fitbit as the processor will be the same, but the features vary. The quickest way to get the work done is:

  • Open the dashboard of the Fitbit charger 3. 
  • Select the calorie burn option.
  • Start the process and let the watch do its work. 
  • Restart or re-pair the watch if the program isn’t working. 

According to the research conducted by universities, it is stated that Fitbit Charge 3 overestimated the result by more than 50%. This means that this device is not that accurate as it claims. 

How Accurate is Fitbit Charge 4 Calorie Burn?

Moving from Fitbit 3 to Fitbit Charge 4 gives you additional features like longer battery backup, brighter lights, better touch but the accuracy rate. Well, let’s discuss that. 

To check the calorie count and calorie burn throughout the day, follow these simple steps:

  • Connect your Android or Apple device with the Fitbit charger 4. 
  • Enter your age, weight, height, and other necessary information required by the Fitbit application.
  • Start the calorie count application and start your activity. 
  • After finishing the activity, stop the process, and the result will be showcased on your mobile screen and watches’ display.

The accuracy is similar to the previous Fitbit charges. However, it is seen that the margin of error is only 27% in the Fitbit Charge 4. So, we can say that the calorie burn feature is improved in the new version. 

How Accurate is Fitbit Charge HR Calorie Burn?

Fitbit Charge HR (Heart Rate) is one of the best heart rate tracking smartwatches with a battery backup of up to 4 days. The calorie burned and calorie count function of Fitbit charge HR is good but not at all accurate. 

  • Just open the feature of the calorie count from the smartwatch screen.
  • Select the feature by holding the button for a few seconds.
  • You will feel the vibrating sensation when the function gets activated.
  • Turn off the function when you end the activity. 

The accuracy rate of Fitbit Charge HR is not as accurate as it should be, and there are some fluctuations in the Calorie count that the company should take care of. The Fitbit Charge HR shows the overestimated result by 5-10%.

How Accurate is Fitbit Charge Flex?

  • To check the calorie count, open the function from the dashboard.
  • Select calorie count.
  • Begin the physical activity.
  • Go to the Fitbit app and open the calorie burn option. 
  • You will find your calorie stats for the given time. 

The accuracy rate is not good as there will be a difference in the result by 20-60%. 

How Accurate is Fitbit Charge Flex 2?

If you think that choosing flex 2 after flex one will give you better accuracy, sorry to disappoint you as they are nearly similar.

  • The calorie count function is the same as you can check through mobile or smartwatch.
  • Start the function and end it after the completion of the activity. 
  • Check the stats and keep it as a record for better transformation. 

The calorie burn accuracy is the same as the previous model, i.e., around 20-50% inaccuracy. 

How Accurate is Fitbit Alta Calorie Burn?

Alta is another model of the Fitbit smartwatch which focuses on Heart rate monitoring and sleep monitoring. However, Fitbit charge Alta is also helpful in monitoring the physical activities, and step counts. 

  • Open the dashboard directly from the watch.
  • Check out the calorie count option.
  • Start by pressing the main button on the watch.
  • The watch will check your heart rate and monitor the calories through your physical activities. 
  • The result will be shown on your connected device and Fitbit’s screen.

In simple words, many people experience that the Fitbit Alta calorie burn option is giving false data and overestimating the result by 40-50%. 

How Accurate is Fitbit Ace 2 Calorie Burn?

Fitbit Ace 2 gives features to the customers like the motion vibrator and step counts. However, you want to find the heart rate monitor or Spo2 monitor on this model. To calculate the calorie, burn and count, follow these steps: 

  • Select the Fitbit application and enter your required information.
  • Go to the calorie count section and select the calorie burn option.
  • Start the process and end the function by completing your physical activities. 
  • The record will be shown in your connected device along with the watch too.

Talking about the calorie burn accurate rate, then the accurate rate is not 100% correct. There are some differences in the results which many users observe. 

Should People Go for the Fitbit Smartwatches?

If we talk about the different smartwatches present in the market, then Fitbit comes in the top 5. The functions and features that this brand offers to the customers make it one of the best choices for people. 

There are so many features that you can enjoy through this device, and they are also available at different price ranges. You can check out the reviews of the watches on the internet and decide which model is preferable for you. 


We hope that “the accuracy report” of each Fitbit Charge smartwatches proves to be helpful for you. We know that the accuracy rate of Fitbit watches is not promising, but they are not that bad either. 

You can use these watches for other purposes as each model gives so many features to the customers, and you can enjoy better battery life in these smartwatches. Now you know how the calorie count function works in every model and how you can check out your calorie during working and running.

If you have a query, feel free to ask them in the comment box, and we are happy to solve them.

Elena Davis

If you are a tech-savvy person, then maybe we have something in common. My name is Elena Davis, and I love everything technology. Testing new wearable technology products and review them is one of my favorite things. I’m contributing my 10+ years experiences in product reviewing for multiple digital brands and companies.

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